The present invention relates to a device for delivering a substance to an internal portion of a body that has been acted on by a procedure performing instrument such as a catheter, trocar, laparoscopic instrument or a biopsy device. The invention more particularly relates to a biopsy device for obtaining one or more tissue samples and for applying at least one substance to the biopsy site in one operation. The biopsy device is particularly adapted to remove a core or segment of tissue from the biopsy site and then apply a surgical adhesive comprised of a first component containing fibrinogen and a second component containing thrombin to the biopsy site to seal the site and control bleeding. If required, multiple tissue samples may be collected before applying the surgical adhesive. The biopsy device described may be operated manually or used in a semi-automatic or automatic mode. The biopsy device may also be adapted to remove a tissue sample from the biopsy site by aspiration.
An excision or coring biopsy is commonly carried out by inserting a needle such as that needle set disclosed in U.S. Pat. No. 3,477,423 into the organ or tissue to be biopsied. That needle is comprised of an outer hollow cutting cannula with an inner stylet needle having a semi-circular notch ground away at the distal end. As the stylet is advanced into the tissue, the tissue is pierced and relaxes or prolapses into the notched cut out or recess. When the cannula is slid forward, the tissue in the notch of the stylet is sliced off and retained in the notch until the cannula is drawn back. The needle yields a core tissue sample which is semi-circular in cross section with its length determined by the length of the notch.
An aspiration biopsy is commonly carried out using an aspiration device known as a Menghini needle as described in U.S. Pat. No. 4,850,373 which is hereby incorporated by reference in its entirety. A biopsy aspirating device is also described in U.S. Pat. No. 3,938,505 which is also incorporated by reference herein in its entirety. In an aspiration biopsy, the Menghini needle or other compatible soft-tissue biopsy aspirating device is directed to the biopsy site and positioned so that the distal end of the needle is located in the tissue or cyst to be biopsied. A syringe is then attached to the proximal end of the needle and tissue or fluid is aspirated from the site. The needle is then withdrawn.
Under certain circumstances, several complications can develop when biopsy samples are collected with known devices. For example, excision biopsies from lung tissue are associated with a relatively high complication rate due to hemorrhage and pneumothorax (McEvey, R. D., Bagley, M. D., Antic. R. 1983: Percutaneous Biopsy of Intrapulmonary Mass Lesions, Cancer 51, 2321). Profuse bleeding is also considered the most important complication associated with excision biopsies of the kidney and other organs. Profuse bleeding can be a particular problem during the biopsy of patients with hemophilia or other clotting disorders as well as those patients under treatment with anti-coagulants such as heparin or coumadin. Aspiration and core biopsies of the liver can also be complicated by profuse bleeding.
To minimize these possible complications, biopsy devices adapted to deliver a surgical adhesive to the biopsy site after aspiration or excision of a tissue sample have been developed. For example, U.S. Pat. No. 4,850,373 is directed to a manual aspiration biopsy device including a two- or multi-lumen biopsy cannula which has a biopsy channel of constant cross-section over its entire length and at least one application channel. On its proximal end, the device is provided with connection facilities for an aspiration device and at least one application device. At least one application channel is formed by a tube eccentrically slipped over the biopsy channel wall. After tissue is collected, a substance such as a blood coagulation material may be introduced directly to the biopsy site.
European Patent 0 455 626 is directed to a manual biopsy device for obtaining a tissue sample and for applying at least one substance in one operation. The biopsy device comprises a biopsy channel having a cutting edge for cutting off tissue and an application channel for applying a blood-clotting substance. The application channel is defined by an application tube slipped over the biopsy cannula. The front end of the application tube is rearwardly offset relative to the cutting edge of the biopsy cannula. At the opposite end of the application channel, a tightly joined connecting piece is provided for connecting at least one duct to convey the blood-clotting substance to the application channel. The biopsy device can be connected to a suction device to collect tissue samples by aspiration. Alternatively, the device can be adapted to perform excision biopsies by longitudinally displaceably mounting a needle with a tissue-penetrating tip within the biopsy cannula as illustrated in U.S. Pat. No. 3,477,423.
The design of the device disclosed in EP 0 455 626 has several potential drawbacks. The clearance between the inner wall of the application tube and the outer wall of the biopsy cannula is small. Consequently, when injecting a substance with a viscous component or components such as a fibrin sealant into the application channel, the user must exert substantial pressure on the injector device to force the components into the application channel for delivery to the biopsy site. As a result, tissue sealant can leak out from the connection between the injector device and the applicator tip. The surgical sealant can also leak out at the connection point between the applicator tip and the cantilevered portion of the connecting tube leading to the application channel.
A second potential drawback of the excision biopsy device disclosed in EP 0 455 626 is contamination of the biopsy sample with the surgical sealant. Since surgical sealant is injected through the application channel while the stylet is still in the biopsy cannula, surgical sealant flows back over the cored tissue sample contained within the biopsy cannula after the surgical sealant is delivered to the biopsy site. As a result, the biopsy sample becomes coated with the surgical sealant such as a fibrin tissue sealant thereby complicating any diagnosis based on analyis of the excised tissue sample.
Theoretically, sample contamination by tissue sealant in the excision biopsy device described in EP 0 455 626 could be avoided by withdrawing the stylet needle containing the excised tissue and the biopsy cannula from the device, leaving only the application tube in place. If the user determined that the tissue sample excised was not of sufficient size or quality for histological examination, the stylet needle could be re-inserted and additional samples obtained. When the biopsy was completed, surgical sealant could then be applied to the biopsy site through the relatively unconstricted application tube. However, withdrawal of the stylet needle/biopsy cannula assembly from the device would provide an unrestricted pathway for blood and sealant to flow back through the application tube by capillary action and severely compromise any attempt by the user to harvest additional biopsy samples or to seal off the biopsy site with a surgical sealant.